The present invention relates to a self-inflatable air cushion for use in shoes, and more particularly to such a self-inflatable air cushion which comprises a collapsible plenum chamber, a support chamber, and an one-way valve connected between the plenum chamber and the support chamber for permitting air to be driven from the collapsible plenum into the support chamber by compressing the plenum chamber with the foot.
A regular air cushion for shoes is generally comprised of a collapsible three-dimensional body defining a plurality of air cells and a plurality of passages connected between the air cells, and an air valve connected to the passages and disposed outside the sole of the shoe. When the air cushion is inflated, an air pump is attached to the air valve and operated to pump air into the air cells. If the inside pressure of the air cushion is excessively high, it cannot be regulated.